1. Field of the Invention
The present invention relates to apparatus and a method for the drilling and re-entry of oil and gas wells in shallow, offshore waters. More specifically, the invention relates to a bottom-setting vessel incorporating a jacking system and a method of using such a vessel and jacking system for transporting and positioning packaged drilling rigs and production facilities.
2. Related Art
Oil and gas wells in shallow offshore waters (that is, water between about 10 feet and 150 feet deep) were initially drilled by means of platform drilling rigs, jack-up rigs, or submersible rigs. In all cases, the wells were outfitted employing a well for operational or safety purposes. Single-caisson, well-protect structures or platforms were employed in the drilling and production operations.
Presently, the re-entry and drilling of offshore prospects are in demand. Early production platforms or "first oil" systems are being employed to eliminate the need to drill new wells, and thus to reduce the time for sales of oil. Because the platforms no longer have drilling rigs, packaged drilling rigs must be brought out to the platforms in order to achieve the desired re-entry. Jacking systems may be used to jack the platform out of the water by using the ocean bottom as the jack base.